Description of Protacanthamoeba

Trophic amoebae indistinguishable from Acanthamoeba. Locomotive form usually between 20 and 40 µm. Nucleus with central nucleolus. Cysts smooth, circular to oval, about 16.5 µm across. Can be distinguished from Acanthamoeba on basis of cyst wall which is without pores and opercula. Freshwater and soil. Type species: P. caledonica Page,